A device management technique for protecting confidential functions of a mobile terminal in a case where the mobile terminal is lost or stolen is disclosed so far. In this technique, the mobile terminal is remotely controlled to change an access control rule or delete data (refer to, for example, JP-A7-193865).
More specifically, methods for configuring a wireless mobile terminal and for ensuring security for the wireless mobile terminal are provided. In such methods, remotely-controlled data is transmitted to the lost mobile terminal from external through a communication line, and thereafter the lost wireless mobile terminal receives the transmitted data and then analyzes contents of the received remotely-controlled data, so that protection processing can be executed to prevent disadvantages of an owner of the wireless mobile terminal.
A first problem of the above-described conventional methods is caused when the following situation occurs. When a mobile terminal is out of communication service or when an unexpected user identity module is installed in a mobile terminal, a remote-control request fails to be delivered. As a result, the mobile terminal cannot be remotely controlled, and thereby a fraudulent access to confidential data or to a confidential function (hereinafter, collectively referred to as “a confidential resource”) may not be prevented. The user identity module (abbreviated as UIM) is an IC card in which a telephone number of a user and information of the user's contracted mobile-service provider are recorded, such as subscriber identity module (SIM), or universal subscriber identity module (USIM). By installing the UIM in the mobile terminal, the mobile terminal can be used with the telephone number recorded in the installed card. Since the remote control request is addressed to an identifier, such as a telephone number, when another UIM is installed, though data bound with the original UIM is locked, it is impossible to delete the data bound with the original UIM or to lock the function bound with the original UIM.
In addition, a second problem is caused when there are a number of mobile terminals to be managed. In this situation, the mobile terminals have to be collectively remote-controlled when an access control rule is changed. Consequently, there is a possibility that the remote control cannot be immediately executed because of loads of a management device or a network. In such a case, there is also a threat that a fraudulent access to a mobile terminal for which the remote control is delayed cannot be prevented. A collective remote control is performed when, for example, an access control for a specific group of mobile terminals such as a place or a time zone, is collectively controlled on the network side, or when a data deletion command is transmitted to all the mobile terminals having confidential data to be deleted.
Accordingly, in light of the above problems, an object of the present invention is to provide a mobile terminal, an access control management device, and an access control management method, which enable to lock an access to a confidential resource even when the mobile terminal is out of service, and enable to prevent concentration of loads when an access control rule is changed.